反应详情

Sodium hydride (60% dispersion in mineral oil, 0.44 g, 7.45 mmol) was added to a suspension of 5-chloro-1H-indole-2-carboxylic acid ethyl ester (2.00 g, 8.94 mmol) in N,N′-dimethylformamide (DMF) (20 ml) under nitrogen. The mixture was stirred for 1 h before addition of the 3-methylbenzyl bromide (2.07 g, 2.48 ml) and the reaction stirred for 17.5 h. Water was added to reaction mixture which precipitated product as a gummy solid. Supernatant liquid was decanted and the solid washed with water. The product was dissolved in dichloromethane (DCM), washed with water, dried over magnesium sulfate and concentrated. Purification by silica chromatography using DCM as eluent, yielded 5-chloro-1-(3-methylbenzyl)-1H-indole-2-carboxylic acid ethyl ester (3.03 g, 95%).

1. customprecipitated product as a gummy solid
2. customSupernatant liquid was decanted
3. washthe solid washed with water
4. dissolutionThe product was dissolved in dichloromethane (DCM)
5. washwashed with water
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated
8. customPurification by silica chromatography